Evaluation of the presence of bovine proteins in human milk as a possible cause of allergic symptoms in breast-fed children

Cow's Milk Antigens Content in Human Milk: A Scoping Review

The functionality of breast milk in terms of immunity is well-known. Despite this, a significant proportion of breastfed infants exhibit sensitization to different potentially allergenic proteins and clinical reactivity (including anaphylaxis) early in life and before the introduction of complementary feeding for the first time. The potential induction of early oral tolerance to overcome early allergic sensitization through exposure to allergens in breast milk also remains controversial and not yet well-established. The objective of this scoping review is to provide a critical appraisal of knowledge about the content of cow’s milk antigens in human milk. The amount of dietary derived milk antigens found in human milk and the analytical methodologies used to detect and quantify these antigens, the allergic status of the mother, the stage of lactation, the time of sampling (before or after ingestion of food), and the impact of human milk allergen on the infant were the outcomes that were assessed. Allergy risk was explored in all reviewed studies and could help to better elucidate its role in the context of allergic disease development. According to the included literature, we can conclude that there are mainly fragments derived from bovine proteins in human milk, and the presence of potentially allergenic molecules is greater in the milk of mothers with an allergic tendency. A clear relationship between maternal diet and allergen content in breast milk could not be firmly concluded though. Also, infants receiving milk from human milk banks, where donor milk is pasteurized for preservation, may be subject to greater risk of allergy development, especially for β-lactoglobulin.

Consensus statement on the epidemiology, diagnosis, prevention, and management of cow's milk protein allergy in the Middle East: a modified Delphi-based study

BACKGROUND

This study aimed to develop an expert consensus regarding the epidemiology, diagnosis, and management of cow's milk protein allergy (CMPA) in the Middle East.

METHODS

A three-step modified Delphi method was utilized to develop the consensus. Fifteen specialized pediatricians participated in the development of this consensus. Each statement was considered a consensus if it achieved an agreement level of ≥ 80%.

RESULTS

The experts agreed that the double-blind placebo-controlled oral challenge test (OCT) should be performed for 2-4 weeks using an amino acid formula (AAF) in formula-fed infants or children with suspected CMPA. Formula-fed infants with confirmed CMPA should be offered a therapeutic formula. The panel stated that an extensively hydrolyzed formula (eHF) is indicated in the absence of red flag signs. At the same time, the AAF is offered for infants with red flag signs, such as severe anaphylactic reactions. The panel agreed that infants on an eHF with resolved symptoms within 2-4 weeks should continue the eHF with particular attention to the growth and nutritional status. On the other hand, an AAF should be considered for infants with persistent symptoms; the AAF should be continued if the symptoms resolve within 2-4 weeks, with particular attention to the growth and nutritional status. In cases with no symptomatic improvements after the introduction of an AAF, other measures should be followed. The panel developed a management algorithm, which achieved an agreement level of 90.9%.

CONCLUSION

This consensus document combined the best available evidence and clinical experience to optimize the management of CMPA in the Middle East.

Maternal Allergy and the Presence of Nonhuman Proteinaceous Molecules in Human Milk

Human milk contains proteins and/or protein fragments that originate from nonhuman organisms. These proteinaceous molecules, of which the secretion might be related to the mother's allergy status, could be involved in the development of the immune system of the infant. This may lead, for example, to sensitization or the induction of allergen-specific tolerance. The aim of this study was to investigate the relation between maternal allergy and the levels of nonhuman proteinaceous molecules in their milk. In this study, we analysed trypsin-digested human milk serum proteins of 10 allergic mothers and 10 nonallergic mothers. A search was carried out to identify peptide sequences originating from bovine or other allergenic proteins. Several methods were applied to confirm the identification of these sequences, and the differences between both groups were investigated. Out of the 78 identified nonhuman peptide sequences, 62 sequences matched Bos taurus proteins. Eight peptide sequences of bovine β -lactoglobulin had significantly higher levels in milk from allergic mothers than in milk from nonallergic mothers. Dietary bovine β -lactoglobulin may be absorbed through the intestinal barrier and secreted into human milk. This seems to be significantly higher in allergic mothers and might have consequences for the development of the immune system of their breastfed infant.

Diagnosis and management of Non-IgE gastrointestinal allergies in breastfed infants-An EAACI Position Paper

It is well-established that food proteins, such as egg, soya, cow's milk and wheat, are detectable in breastmilk for many hours or days after ingestion. Exposure to these proteins is important to the process of developing tolerance but can also sometimes elicit IgE-mediated and non-IgE-mediated allergic symptoms in breastfed infants. Non-IgE-mediated allergy, outside of food protein-induced allergic proctocolitis and eosinophilic oesophagitis, is not well understood, leading to variations in the diagnosis and management thereof. A primary objective of the European Academy for Allergy and Clinical Immunology is to support breastfeeding in all infants, including those with food allergies. A Task Force was established, to explore the clinical spectrum of non-IgE-mediated allergies, and part of its objectives was to establish diagnosis and management of non-IgE-mediated allergies in breastfed infants. Eight questions were formulated using the Patient, Intervention, Comparison, Outcome (PICO) system and Scottish Intercollegiate Guideline Network (SIGN) criteria for data inclusion, and consensus was achieved on practice points through the Delphi method. This publication aims to provide a comprehensive overview on this topic with practice points for healthcare professionals.

Donkey milk as a supplement in infant formula: Benefits and technological challenges

The aim of this review paper is to assess the applicability of donkey's milk to infants suffering from Cow Milk Protein Allergy (CMPA) compared to human and other available milk types. The bioactive and immune-supportive character which could be beneficial as a fortifier to the formula-fed infants is described while limitations of this type of milk are also discussed. Studies showed that human and donkey's milk have similar, overall, chemical composition as well as protein homogeneity and antigenic similarities. Several in vitro and in vivo studies showed that donkey's milk has nutraceutical and functional properties that can support immunity, alter metabolism and beneficially modify gut microbiota. Clinical studies illustrated that donkeys' milk is well tolerated (82.6%-88%) by infants. Finally, the effect that processing (i.e. thermal, non-thermal treatments, drying methods) has on donkey milk components is also discussed pointing out the need for minimally processing this type of milk.

Antibody-independent identification of bovine milk-derived peptides in breast-milk

Exclusively breast-fed infants can exhibit clear signs of IgE or non IgE-mediated cow's milk allergy. However, the definite characterization of dietary cow's milk proteins (CMP) that survive the maternal digestive tract to be absorbed into the bloodstream and secreted into breast milk remains missing. Herein, we aimed at assessing possible CMP-derived peptides in breast milk. Using high performance liquid chromatography (HPLC)-high resolution mass spectrometry (MS), we compared the peptide fraction of breast milk from 12 donors, among which 6 drank a cup of milk daily and 6 were on a strict dairy-free diet. We identified two bovine β-lactoglobulin (β-Lg, 2 out 6 samples) and one αs1-casein (1 out 6 samples) fragments in breast milk from mothers receiving a cup of bovine milk daily. These CMP-derived fragments, namely β-Lg (f42-54), (f42-57) and αs1-casein (f180-197), were absent in milk from mothers on dairy-free diet. In contrast, neither intact nor hydrolyzed β-Lg was detected by western blot and competitive ELISA in any breast milk sample. Eight additional bovine milk-derived peptides identified by software-assisted MS were most likely false positive. The results of this study demonstrate that CMP-derived peptides rather than intact CMP may sensitize or elicit allergic responses in the neonate through mother's milk. Immunologically active peptides from the maternal diet could be involved in priming the newborn's immune system, driving a tolerogenic response.

Review article: the diagnosis and management of food allergy and food intolerances

BACKGROUND

Adverse reactions to food include immune mediated food allergies and non-immune mediated food intolerances. Food allergies and intolerances are often confused by health professionals, patients and the public.

AIM

To critically review the data relating to diagnosis and management of food allergy and food intolerance in adults and children.

METHODS

MEDLINE, EMBASE and the Cochrane Database were searched up until May 2014, using search terms related to food allergy and intolerance.

RESULTS

An estimated one-fifth of the population believe that they have adverse reactions to food. Estimates of true IgE-mediated food allergy vary, but in some countries it may be as prevalent as 4-7% of preschool children. The most common food allergens are cow's milk, egg, peanut, tree nuts, soy, shellfish and finned fish. Reactions vary from urticaria to anaphylaxis and death. Tolerance for many foods including milk and egg develops with age, but is far less likely with peanut allergy. Estimates of IgE-mediated food allergy in adults are closer to 1-2%. Non-IgE-mediated food allergies such as Food Protein-Induced Enterocolitis Syndrome are rarer and predominantly recognised in childhood. Eosinophilic gastrointestinal disorders including eosinophilic oesophagitis are mixed IgE- and non-IgE-mediated food allergic conditions, and are improved by dietary exclusions. By contrast food intolerances are nonspecific, and the resultant symptoms resemble other common medically unexplained complaints, often overlapping with symptoms found in functional disorders such as irritable bowel syndrome. Improved dietary treatments for the irritable bowel syndrome have recently been described.

CONCLUSIONS

Food allergies are more common in children, can be life-threatening and are distinct from food intolerances. Food intolerances may pose little risk but since functional disorders are so prevalent, greater efforts to understand adverse effects of foods in functional disorders are warranted.

Session 1: Allergic disease: The challenges of managing food hypersensitivity

Food hypersensitivity (FHS) is the umbrella term used for food allergies that involve the immune system and food intolerances that do not involve the immune system. FHS has a huge impact on quality of life and any dietary advice given should aim to minimise this effect. Despite many advances made in diagnosing and managing patients with FHS, the cornerstone of management still remains avoidance of the relevant food. However, a commonly-presenting dilemma in clinical practice is deciding to what extent the food(s) should be avoided. The level of avoidance required is currently based on the type of FHS the patient has, characteristics of the particular food protein and the natural history of the particular FHS. In addition to management of other FHS, management of cow's milk allergy requires the healthcare professional to choose the appropriate formula. Information required by the patient also includes understanding food labels and issues surrounding cross-contamination. In order to ensure that the diet is nutritionally sound, advice should be given about suitable food choices and following a healthy balanced diet, whilst taking into account the dietary restrictions. Practical issues that need to be addressed include going on holiday, travelling and eating away from home. The dietitian plays a crucial role in this process. At present, there are no standardised documents or protocols for the management of FHS and practices differ within and between countries. If adrenaline auto-injectors are prescribed, correct administration should be demonstrated and reviewed on an ongoing basis.

Management of cow's milk protein allergy in infants and young children: an expert panel perspective

Cow's milk protein allergy is a condition commonly managed by general practitioners and paediatricians. The diagnosis is usually made in the first 12 months of life. Management of immediate allergic reactions and anaphylaxis includes the prevention of accidental food ingestion and provision of an adrenaline autoinjector, if appropriate. By contrast, the clinical course of delayed food-allergic manifestations is characterised by chronicity, and is often associated with nutritional or behavioural sequelae. Correct diagnosis of these non-IgE-mediated conditions may be delayed due to a lack of reliable diagnostic markers. This review aims to guide clinicians in the: (i) diagnostic evaluation (skin prick testing or measurement of food-specific serum IgE levels; indications for diagnostic challenges for suspected IgE- and non-IgE-mediated food allergy), (ii) dietary treatment, (iii) assessment of response to treatment, (iv) differential diagnosis and further diagnostic work-up in non-responders, (v) follow-up assessment of tolerance development and (vi) recommendations for further referral.

Gastrointestinal food allergy and intolerance

GI symptoms are a common manifestation of food allergy and intolerance. The primary physician is the first to evaluate these symptoms. A systematic evaluation using an accurate and detailed history, tests to identify the offending food(s), and procedures that may identify underlying pathologic disorders of the GI tract would lead to an accurate diagnosis and better targeted therapeutic interventions.

The role of cow milk allergy in increasing the severity of atopic dermatitis

Previous studies have shown that up to 33% of children with atopic dermatitis have experienced food hypersensitivity and among different kinds of food allergens Cow Milk (CM) has almost always been one of the most common food allergens in children. The aim of this study is to evaluate the cow milk allergy (CMA) as an increasing factor of severity of atopic dermatitis. One hundred and nineteen children (between 1.5 months and 12 years of age) with atopic dermatitis in the sense of Hanifin and Rajka's criteria entered this study and the severity of atopic dermatitis was identified via the SCORAD index. In order to make the diagnosis of cow milk allergy, a careful history, and a familial history of allergy was taken and the results of skin prick test (SPT) with CM and 4 other food allergen extracts, Radioallergosorbent test (RAST) with CM allergens and a food challenge test with cow milk (fresh or dried) were used. Also a total serum IgE determination and an eosinophil count (with a stool exam) were accomplished. The clinical manifestations of atopic dermatitis in patients was started from their first day of life up to 10 years of age. The family history in 83% of the patients was positive. Positive skin prick test and RAST with CM allergens were positive in 37.9% and 29.3% of cases respectively and the response to challenge test with cow milk was positive in 35 out of 40 patients and in total 44.5% had CMA according to a positive history of cow milk allergy and a positive outcome of the IgE tests (SPT and/or RAST) or a positive challenge test with CM allergens. The results showed that the most common food allergens in patients with atopic dermatitis are certainly cow milk allergens (44.5%) whereas other food allergens are tomato (29.41%), egg (28.57%), nuts (9.24%) and wheat (3.36%) according to the skin prick test. The mean total serum IgE was 307.11 +/- 6.56 IU/ml (range = 6-5000) in children with CMA and 81.04 +/- 5.97 IU/ml (range = 1-5000) in children without CMA while the mean eosinophil count was 569.52 +/- 3.02 count/ml (range = 67-8500) and 314.22 +/- 2.94 count/ml (range = 5-5000) respectively. The mean severity of atopic dermatitis according to the SCORAD index was 60.76 in children with CMA and 44.29 in children without CMA. The severity of atopic dermatitis in patients with CMA was significantly higher than patients without CMA (p < 0.0001). Also the mean total serum IgE and mean eosionophil counts in children with CMA were significantly higher than in children without CMA (P < 0.01 and p < 0.0001, respectively). It shows the important role of CM allergen proteins in the induction and in increasing the severity of AD in children.

Therapeutic modalities for cow's milk allergy

OBJECTIVE

To discuss current therapeutic modalities for cow's milk allergy and its prevention.

DATA SOURCES AND STUDY SELECTION

The sources of data include original clinical studies carried out at Ste. Justine Hospital, as well as a systematic search of the published English and French language scientific literature restricted to human subjects using computerized searches (National Public Library of Medicine, Cochrane Database Systems Review) from 1997 to 2002. Search terms for article retrieval included food allergy, milk allergy, therapy, and prevention.

CONCLUSIONS

The therapy of food allergies depends upon an accurate diagnosis, which remains a challenge in non--IgE-mediated cases. Dietary exclusion remains the mainstay of therapy, with medications reserved for exceptional patients. Preliminary evidence suggests that pancreatic enzyme supplementation may be of benefit for cases with multiple food allergies and severe eczema. Hydrolysate formula use is currently recommended for dietary allergy prevention in infants at an increased risk when maternal milk is insufficient or unavailable. The use of partially hydrolyzed formulas to prevent allergic disorders, including atopic dermatitis, is supported by clinical studies, but cannot be used in the already sensitized, milk-allergic child. Probiotics show enormous potential in preventing food allergic disorders as well.

Cow's milk allergy in infancy

Cow's milk allergy affects approximately 2% of infants under 2 years of age. This review summarizes the recent advances in understanding its pathophysiology and immunological mechanisms. Apart from IgE-mediated atopic manifestations, T cell-mediated reactions have been demonstrated in infants with cow's milk allergy. The clinical spectrum ranges from immediate-type reactions, presenting with urticaria and angioedema to intermediate and late-onset reactions, including atopic dermatitis, infantile colic, gastro-oesophageal reflux, oesophagitis, infantile proctocolitis, food-associated enterocolitis and constipation. The exact mechanisms of these disorders are still poorly understood. Double-blind, placebo controlled food challenge, the definitive diagnostic test for cow's milk allergy, is increasingly being replaced by the measurement of food-specific antibodies, in combination with skin-prick or atopy patch testing. The treatment of cow's milk allergy relies on allergen avoidance and hypoallergenic formulae, or maternal elimination diets in breast-fed infants.